On Wed, 26 Jul 2006, Manfred Spraul wrote: > > Thus the patch is correct, it's a bug in the slab allocator. If > > HWCACHE_ALIGN > > > is set, then the allocator ignores align or ARCH_SLAB_MINALIGN. > > > > > > But then Heiko does not want to set ARCH_SLAB_MINALIGN at all. This is not > > the issue we are discussing. In the DEBUG case he wants > > ARCH_KMALLOC_MINALIGN to be enforced even if ARCH_SLAB_MINALIGN is not set. > > > The kmalloc caches are allocated with HWCACHE_ALIGN+ARCH_KMALLOC_MINALIGN. The > logic in kmem_cache_create didn't handle that case correctly. > On most architectures, ARCH_KMALLOC_MINALIGN is 0. Thus SLAB_DEBUG redzones > everything. > On s390, ARCH_KMALLOC_MINALIGN is 8. This disables redzoning. > > Ok? So Redzoning etc will now be diabled regardless even if ARCH_SLAB_MINALIGN is not set but another alignment is given to kmem_cache_alloc? So we sacrifice the ability to worsen the performance of slabs by misaligning them for debugging purposes. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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